Astra Sailor 1: X1

The original plan for the Astra Sailor Program was to create a Single Stage To Orbit platform that could travel interplanetary. Although it was able to get to Minmus, It was without a payload. Thus, the idea for a Single Stage to Orbit was scrapped.

Astra Sailor 2: X2

After a Jet-Powered Astra Sailor was canceled, funding was redirected to a spaceplane similar to the NASE Program. As a result, the Sailor ship was created, and was tested in it's first ever glide test. The results of this glide were promising.

Astra Sailor 3: X3

Now that the Astra Sailor could glide, it was put on a sub-orbital trajectory to test if it could survive re-entry. During re-entry, the spacecraft got near it's maximum temperature, but never reached it. Thus, it passed the test.

Astra Sailor 4: X4

Following it's atmospheric tests, the Astra Sailor was launched on Super-Sailor, which is the main rocket that is to launch Astra Sailor into orbit, then return for an automated landing. Astra Sailor was able to make it to orbit on this test, and Super-Sailor was able to touch down back at Kerbin, showing it is fully reusable.

Astra Sailor 5-6: Eve

Now that Astra Sailor was able to launch heavy payloads into orbit while retaining enough fuel to reach any planet, a request was made by the Kerbelian Government to put a space station in orbit of Eve to research the possibility of life. Along with this, it would act as a space outpost for future missions. This showed that Astra Sailor was ready for regular use.

Astra Sailor 7: Laythe Foundation

With the looming threat of the Syracrusian's and their nuclear warheads, the Kerbelian Government funded a program to find a celestial body that could host the future of Kerbalian life. Laythe, the water world of Jool, was selected as the prime target. Past readings of the planet showed that it was perfect for life, thus Astra Sailor was sent to drop off a colony, and come back.

Astra Sailor 9: Vall

Now that Laythe has been colonized by Kerbals, they decided to look at other moons of Jool for prospecting interests. Thankfully, Vall had volcanic activity, and N.S.P. wanted to investigate. As a result, Astra Sailor was manufactured and launched off of Laythe, resulting in it becoming N.S.P.'s first rocket to launch off of another world. This mission solidified Astra Sailor as the Work Horse of N.S.P.